This dissertation is an autosegmental analysis of the tonal patterns manifested in the verb of Setswana, a Southern Bantu language spoken in Botswana and South Africa. Verbal tone in this language is very complex because the tonal patterns fluctuate, depending on many factors. These factors include, but are not limited to, for example, the syntactic environment in which the verb occurs, and the type of morpheme, high or toneless, that precedes the verbstem. The matter is further complicated by the fact that there are two types of verbstems in Setswana, namely, high-toned versus toneless (low-toned). All of these factors taken together result in the variability of verbal tonal patterns attested in this language.The aim of this study, is to offer an analysis of what may be viewed in the literature on tonal studies as evidence that Setswana verbal tonal patterns violate the phonological principle termed the Obilgatory Contour Principle (OCP). The OCP is assumed to be a universal principle by most authors who subscribe to its existence. According to this principle identical features cannot exist side by side. In the case of Setswana tone, the implication is that a sequence of high tones is prohibited. The very presence of these tonal sequences in Setswana presents a case that the OCP does not hold for this language. We disprove this fact by appealing to a weaker version of the OCP whereby sequences of singly-linked high tones are allowed whereas sequences of multiply-linked high tones are not allowed. The conclusion reached is that the OCP is a parametrical principle whose manifestation is dictated by any particular language.